Bond Dissociation Energy (BDE)Chemistry

Bond Dissociation Energy (BDE) & Reaction Enthalpy Calculator

Estimate gas-phase reaction enthalpies (ΔH in kJ/mol) from average covalent bond dissociation energies by balancing energy input for bond cleavage against energy released in bond formation.

Calculated Result

Estimated Reaction Enthalpy (ΔH)

-486kJ/mol

Calculator Inputs

kJ/mol
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kJ/mol
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Estimated Reaction Enthalpy (ΔH)

-486kJ/mol

Absolute Energy Magnitude

0 kJ/mol

Exothermic Process: The newly formed product bonds are significantly stronger and more stable than the reactant bonds cleaved.

Bonds Broken vs Bonds Formed Energy Balance

Bonds Broken (+)
1,370 kJ/mol(42%)
Bonds Formed (-)
1,856 kJ/mol(58%)

Standard molecular thermochemistry tool for covalent bond energy accounting in gas-phase reactions.

Calculation Methodology

Reaction Enthalpy: ΔH_rxn = Σ [ Energy of Broken Reactant Bonds ] - Σ [ Energy of Formed Product Bonds ]. Breaking bonds is strictly endothermic (+); forming bonds is strictly exothermic (-).

Frequently Asked Questions

Chemical bonds exist at an electrostatic potential energy minimum; pulling atoms apart requires energy input, while bringing them together releases potential energy.

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